Even when lawyers are not given express or explicit authorization by a client, a client’s lawyer is generally presumed to have authority to settle a case on a client’s behalf. Express authority to settle is presumed when an attorney expressly asserts such authority. Eaton v. Mallinckrodt, Inc., 224 S.W.3d 596, 599 (Mo. 2007). Moreover, even in the absence of an express statement, authority is presumed when an attorney undertakes negotiations with the opposing party or lawyer. Kenney v. Vansittert, 277 S.W.3d 713, 721 (Mo. Ct. App. 2008).
Although usually raised in the context of a motion to enforce settlement, Missouri generally only permits parties to avoid settlements reached by their attorneys “where the evidence has failed to raise this presumption of authority or where the fact-finder is truly convinced authority is lacking.” Id.